JP2515916B2 - Composition for gap filling material for civil engineering and construction work, gap filling material for civil engineering and construction work, and construction method using the gap filling material - Google Patents

Description

TECHNICAL FIELD The present invention relates to a composition for a space filling material for civil engineering and construction work, which contains a highly expandable zeolite as a component, a space filling material for civil engineering and construction work, and the space filling material. Regarding the construction method.

Conventional technology In civil engineering and construction work, the backfill injection material and filling material for voids such as voids and cavities are mainly cement and a mixture of gravel, sand, clay, etc. Various materials such as a foaming agent for introducing a gas, a foaming agent for generating a gas by a chemical reaction, and a material having a quick-setting property are used. Among them, those to which a foaming agent or a foaming agent has been added are excellent in flowability, pumpability, material separability, economical efficiency, etc.

This foaming agent physically introduces air bubbles during the kneading of materials by the action of surface activity, such as rosin soap, anionic surface active agents, nonionic surface active agents, protein derivatives such as gelatin and casein, and alkyl sulfonic acid. It is mainly composed of salt. However, these foaming agents have different foaming conditions depending on the amount of addition and the kneading conditions such as the size of the mixer, the shape of the blades, the number of rotations of the blades, and the stirring time. It is difficult to keep the quality constant at all times, and it is difficult to obtain uniform air bubbles because the air bubbles are physically introduced during the material kneading. Although large bubbles tend to collect, there is a drawback in that the volume is reduced and cavities are easily formed, making it difficult to close the cells.

On the other hand, as the foaming agent, aluminum powder is typically used, and also a two-component system such as hydrogen peroxide-calcium hypochlorite and hydrochloric acid-sodium bicarbonate is used. However, aluminum powder is generally used in mortar for prepacked concrete, grout for prestressed concrete, aerated concrete, etc., and although the amount used is only about 0.01% with respect to the cement weight, aluminum powder is used as a gap filling agent. When used, several times to several tens of times the amount used for the above application is required, and when the addition amount of the aluminum powder is increased, foaming starts to occur more rapidly than a certain time and it becomes extremely difficult to control the foaming amount, Due to the heat generated by foaming, the curing time of the filling material itself is shortened, and due to a sudden rise in foaming pressure, it causes unexpected damage to the construction frame such as the tunnel frame, making it impossible to obtain a uniform foamed solid body. The agent is one that generates hydrogen gas, for example, metal aluminum powder is Since hydrogen gas is generated by the reaction, it is difficult to handle because of the danger of explosion of hydrogen gas, which has a low explosion limit, and metal alkali is a dangerous material that may cause a fire, which makes workability difficult. It has the drawback of being.

Therefore, there is a strong demand for the development of a foamable material that does not have such drawbacks and that foams a safe gas and that foaming does not suddenly occur in a short time.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The present invention overcomes the drawbacks of the gap filling material in the conventional civil engineering and construction work, the foaming gas is safe, the foaming is performed relatively slowly, and the foaming amount is large. A foaming material is used as a composition component, it does not cause rapid foaming and curing during operation, it has good workability, it has excellent uniformity after solidification, it can fill gaps without excess or deficiency, and it is safe and has a large amount of foaming. The purpose of the present invention is to provide a gap filling material, a composition for the filling material, and a construction method using the filling material.

Means for Solving the Problems The present inventors have conducted various studies in order to develop a gap filling material for civil engineering and construction work having the above-mentioned preferable characteristics, and as a result, zeolite is burned to a predetermined temperature and dried in a predetermined air temperature. What is forcibly cooled below the temperature functions as an extremely excellent foaming agent by generating a remarkably large amount of bubbles relatively slowly when water is added, and such a high blending ratio of such a highly expandable zeolite and a condensation hardening agent The composition can be prepared into an excellent gap filling material by adding a predetermined proportion of water to it, and by performing gap filling construction in civil engineering and construction work using this filling material, breathing is suppressed during construction and foaming is relatively It was found that it is carried out slowly, the workability is good, the uniformity after consolidation is excellent, and an extremely large amount of foaming can be safely obtained, and the present invention is based on these findings. Came to make.

That is, the present invention, 60-90 wt% of the setting hardening material, after firing the zeolite to 100 ~ 700 ℃, in dry air, 10
C composition for gap filling material for civil engineering and construction work, which is composed of a mixture with highly expandable zeolite 10 to 40 wt% prepared by forced cooling to a low temperature of not more than 0 ° C., for this composition,
It is intended to provide a gap filling material for civil engineering and construction work, which comprises 10 to 100% of water on a weight basis, and a construction method characterized by filling the gap filling material with the gap in civil engineering and construction work.

The highly expandable zeolite used in the present invention can be obtained by calcining zeolite to 100 to 700 ° C, preferably 400 to 600 ° C, and then forcibly cooling it to a low temperature of 10 ° C or less in dry air. At this time, the forced cooling may be performed after firing, after allowing to cool, or after gradually cooling to room temperature, or after allowing to cool and further gradually cooling to room temperature. The zeolite used as the raw material may be either natural zeolite or synthetic zeolite, but natural zeolite is preferred. Zeolite is usually used after being pulverized and classified to have a predetermined particle size. The amount of foaming increases remarkably by forced cooling. For example, FIG. 1 is a graph showing the relationship between the forced cooling temperature of zeolite calcined at 500 ° C. and the amount of foaming,
From this, it can be seen that the foaming amount increases as the forced cooling temperature decreases. In this way, the foaming amount can be adjusted by changing the forced cooling temperature. The forced cooling is performed by a conventional method, for example, a method of holding in a freezer warehouse under a predetermined condition, for example, a predetermined temperature for a predetermined time.

Zeolite has a crystal structure in which the tetrahedra of silicate SiO ₂ are polymerized, and a foaming gas such as nitrogen or water is usually taken into the space inside the crystal, and the water in it is at an appropriate temperature. It is presumed that it will be replaced by nitrogen and the like in the air by firing at. The foaming mechanism is based on the effect that the foaming gas such as nitrogen is replaced with water and the foaming gas such as nitrogen gas is generated, and the fine bubbles of this gas are uniformly generated in the material. It is speculated that foamed solids are produced. Nitrogen gas is a stable gas, and because it is nonflammable, there is no risk of explosion.

The composition for gap filling material for civil engineering and construction work of the present invention is obtained by mixing the highly expandable zeolite and the setting hardening material, and the mixing ratio is the former 10 to 40% by weight and the latter 60 to 60% by weight.
It is selected in the range of 90% by weight.

The setting and hardening material is, for example, at least one kind of aggregate such as cement, gypsum, lime, slaked lime, or a mixture thereof, or fine aggregate such as sand, coarse aggregate such as gravel and gravel, or clay. , At least one kind of filler such as fly ash, slag and shirasu, or a composition prepared by mixing both of these aggregates and filler.

Further, in the composition for filler, at least one selected from a foaming agent, a foaming agent, a quick-curing additive and a viscosity-imparting agent can be blended as an admixture.

The foaming agent may be any as long as it can physically introduce bubbles, and examples thereof include those containing an anionic surfactant, a nonionic surfactant or an alkyl sulfonate as a component. .

Further, the foaming agent may be any as long as it can generate a gas by a chemical reaction, and for example, aluminum powder, magnesium powder or the like is used.

Further, the rapid hardening additive is not particularly limited as long as it can impart rapid hardening, for example, water glass, aluminate,
As the main component, a quick-setting inorganic salt such as carbonate such as sodium carbonate and at least one quick-setting agent such as calcium sulfoaluminate are used.

The viscosity-imparting agent is not particularly limited as long as it can impart viscosity, and examples thereof include clay minerals such as bentonite and sepiolite, and organic thickeners such as carboxymethyl cellulose, cellulose ether compounds, and acrylic polymer compounds. Are used.

The void filling material for civil engineering and construction work of the present invention is made by mixing water with the filling material composition, and the mixing ratio of water is based on the weight of the mixture of the highly expandable zeolite and the setting hardening material.
It is selected in the range of 10 to 100%, preferably 15 to 70%.

Of these gap filling materials, the simplest composition is
60-90% by weight of setting hardening material and 100-700 ℃ of zeolite,
Preferably after firing at 400 ~ 600 ℃, in dry air, 10
Produced by adding 10 to 100% by weight of water, preferably 15 to 70% by weight, to a mixture with 10 to 40% by weight of highly expandable zeolite prepared by forced cooling to a low temperature below ℃ be able to.

In the present invention, the proportion of the high-expanding zeolite in the mixture of the high-expanding zeolite and the setting hardening material is less than 10% by weight, at the time of construction, the amount of foaming is small and the effect of the present invention is not sufficiently exerted, and also 40% by weight. If it exceeds%, the strength is unavoidably reduced.

On the other hand, if the ratio of water to the mixture is less than 10% by weight, slurrying is insufficient and the effect of the present invention is not sufficiently exhibited, and if it exceeds 100% by weight, the strength is unavoidably reduced.

The gap filling material of the present invention is filled in a gap in civil engineering work and construction work, and this "gap" means
Means voids, cavities or defects that should be repaired or reinforced, such as voids between tunnel linings and ground, voids in the back of underground structures, voids caused by subsidence, voids or voids in the ground, underground Examples include voids in the backfill area associated with buried works.

The above filler composition can be used to prepare a desired gap filler by adding water, as described above, in civil engineering work or construction work, that is, civil engineering work. At this time, it is preferable to sufficiently knead.

The gap filling material thus obtained usually has a foaming ratio of 1
~ Continue for about 5 hours, but about 5 to 20 minutes after kneading, the foaming amount will be about 50 to 80% of the final foaming amount.
Even if the filling material is filled up due to the foaming reserve capacity of about%, the filling material expands and intrudes into the small voids, so that good filling performance can be obtained.

For example, when filling a cavity on the backside of a tunnel lining, generally consider the effect on the lining and set the injection pressure to 2-3 k
Filling is managed with gf / cm ² as a relatively small value, but if cracks occur in the lining or if the winding thickness is insufficient, the injection pressure is restricted to a smaller value. However, with such a small injection pressure, it is difficult to perform sufficient filling, and there is a risk of leaving an unfilled portion even after filling. Therefore, post-filling property is demanded in order to make up for such a lacking filling part.

The filling material of the present invention is filled in a gap in civil engineering work and construction work, and slowly foams for several tens of minutes during the gap filling construction, so that it continues to foam even after injection, so there is no influence on the lining. Even if the injection is completed under a small injection pressure, good filling can be expected due to the subsequent foaming of the filling material. Moreover, the foaming pressure of the filling material is very small (1 kgf / cm ² or less), and unlike the filling material that uses aluminum powder that produces a foaming pressure of several kgf / cm ² or more, there is concern about the effect on the lining. There is no. Also,
Since the bubbles generated by foaming are fine and rich in uniformity,
Like the one using a conventional foaming agent, the bubbles in the surface layer part escape,
The risk of volume reduction is extremely low. Therefore,
The filling material of the present invention is extremely suitable for purposes such as backfilling of tunnel linings, reinforcement of linings, and filling of gaps in the back surface of underground structures.

The characteristics of the filling material of the present invention will be described with reference to the accompanying drawings. FIG. 2 shows the mixing ratio of zeolite to cement and the foaming amount for a filling material in which the ratio of water to the total amount of cement and zeolite is 60% by weight. It is a graph which shows a relationship.

From this, by increasing the content of zeolite,
Up to a certain point, for example, in the case of FIG.
It can be seen that the foaming amount increases to a relatively large value up to 0.1, but beyond that, even if the amount of zeolite is increased, the foaming amount does not increase so much.

In addition, FIG. 3 shows the following A-containing various foaming substances.
A graph showing the relationship between the foaming amount and the time elapsed since the filler was prepared by kneading the composition for void filling material of 1, A-2, X and Y together with 60% by weight of water by weight. Indicate. A-1 and A-2 are for reference of the filler of the present invention, and the weight ratio of cement and calcined zeolite calcined to 500 ° C. and cooled to 20 ° C. is 2: 1 in the former case, the latter is the latter. 5: 1, X and Y are for comparison, and X is a composition prepared by adding 0.3% by weight of a foaming agent (Sanko Colloid Co., Ltd., Sanko GP) to cement. , Y is a composition prepared by mixing 0.03% by weight of aluminum with respect to cement.

From this graph, when the conventional foaming agent is used, there is almost no change in the foaming amount over time, and when the conventional foaming agent is used, the foaming amount increases rapidly after 3 minutes. On the other hand, in the composition for void filling material using zeolite for reference of the filling material of the present invention, after 10 minutes, about 60 to 70% of the final foaming amount is foamed, and the remaining 40 to 30% foaming amount. It can be seen that the foaming gradually progresses, and the filling material penetrates into the underfilled portion and the small voids even after the filling construction work, and an excellent filling effect is obtained.

The filling material of the present invention is more excellent because it can obtain a filling effect similar to that of the reference material and can perform a larger amount of foaming than this filling material.

Next, the filler of the present invention obtained by adding 60% by weight of water to a mixture consisting of 5 parts by weight of cement and 1 part by weight of highly expandable zeolite was kneaded at 140 rpm with a mixer to obtain a casting mold. It was placed in a container and left for 1 day to be solidified. The breathing amount and foaming amount generated in this process were measured.
In addition, the whole solidified product was cut into upper, middle, and lower three layers, and the average unit volume weight of each was determined. The results are shown in the table.

Also, for comparison, with respect to the cement, 60% by weight of water and 0.03% by weight of aluminum powder are mixed to form a gap filling material (hereinafter referred to as Comparative Sample 1) and the cement,
About 60% by weight of water and 0.03% by weight of a foaming agent (Sanko Colloid Co., Ltd., trade name Sankou GP), a gap filling material (hereinafter referred to as Comparative Sample 2) was solidified in the same manner as the above filling material. The amount of breathing, the amount of foaming, and the average unit volume weight of the upper, middle, and lower three layers were determined. The results are also shown in the table.

As a result, Comparative Samples 1 and 2 both had a large amount of breathing, and in the case of Comparative Sample 2, the lower layer had a higher average unit volume weight, and the uniformity over the entire filler after consolidation was higher. Inevitably, the filler of the present invention has a small amount of breathing and is excellent in uniformity after consolidation.

Effects and Effects of the Invention The filler composition of the present invention foams a safe gas in a large amount and relatively slowly when a predetermined amount of water is added, and the filler thus obtained fills voids in civil engineering and construction work. It is used for construction, is safe, has a small amount of breathing, foaming progresses relatively slowly, foaming pressure is moderate, workability is good, gap filling can be done without excess or deficiency, and even after consolidation. It is excellent in properties and has a remarkable effect that an extremely large amount of foaming can be obtained.

Therefore, this filling material is used for civil engineering and construction work, especially for backfilling of tunnel linings and reinforcement of linings, filling of cavities caused by gaps in the back of underground structures and ground subsidence, soft ground improvement work, especially soft ground. It can be suitably used for filling voids in the ground in compaction injection work, etc., and for backfilling in underground works.

[Brief description of drawings]

FIG. 1 is a graph showing the relationship between the cooling temperature of the calcined zeolite and the foaming amount, and FIG. 2 is a graph showing the relationship between the compounding ratio of zeolite to the cement of one example of the filler of the present invention and the foaming amount. FIG. 3 is a graph showing the relationship between the elapsed time from the preparation of various fillers and the foaming amount.

Claims (7)

(57) [Claims] 1. A setting hardening material of 60 to 90% by weight and zeolite.
Composition for gap filling material for civil engineering and construction work consisting of a mixture with 10-40% by weight of highly expandable zeolite prepared by forcibly cooling to a low temperature of 10 ° C or less in dry air after firing at 100-700 ° C Stuff. 2. The setting hardening material is formed by mixing at least one kind of aggregate with at least one kind of inorganic hardening material selected from cement, gypsum, lime and slaked lime. Composition. 3. The composition according to claim 1, further comprising an admixture comprising one or both of a foaming agent and a foaming agent. 4. A quick-curing additive containing at least one quick-setting agent selected from water glass, inorganic aluminate, quick-setting inorganic salt and calcium sulfoaluminate as a main component. The composition according to claim 1, 2 or 3, which comprises: 5. The composition according to any one of claims 1 to 4, which comprises a viscosity-imparting agent comprising one or both of a clay mineral and an organic thickener. 6. The composition according to any one of claims 1 to 5, which is 10 to 10 on a weight basis of the mixture according to claim 1.
A space filling material for civil engineering and construction work that is composed of 100% water. 7. A construction method comprising filling the gap filling material according to claim 6 in a gap in civil engineering and construction work.